Tryit Editor v2.7

Edit This Code:
<!DOCTYPE html>
<html>
<body>

Date: <input type="date" id="myDate">

<p>Click the button to change the value of the step attribute of the date field.</p>

<p><b>Tip:</b> Open the calendar on the right side of the date field before and after you click the button, to see the effect.</p>

<button onclick="myFunction()">Try it</button>

<p><strong>Note:</strong> input elements with type="date" are not supported in Internet Explorer or Firefox.</p>

<p id="demo"></p>

<script>
function myFunction() {
    document.getElementById("myDate").step = "2";
    document.getElementById("demo").innerHTML = "Step was set to '2', meaning that the user can only select every second day in the calendar.";
}
</script>

</body>
</html>